bug#54802: OClosure: Make `interactive-form` a generic function

[Eli Zaretskii]

> Cc: 54802@debbugs.gnu.org
> Date: Fri, 15 Apr 2022 12:08:04 -0400
> From:  Stefan Monnier via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> Eli and Lars, do you prefer the faster-but-uglier API or the
> cleaner-but-slower API for `interactive-form`?

As I said up-thread, I don't understand why we need to touch
interactive-form at all.